body{
	padding-top:10px;
}
.all_bg{
	width:800px;
	height: 550px;
	margin:0 auto;
}
#all_canvas{
	position: relative;
	width:800px;
	height: 550px;
	margin:0;
}
#canvas1{
	position: absolute;
	bottom: 0;
	left: 0;
	z-index: 1;
}
#canvas2{
	position: absolute;
	bottom: 0;
	left: 0;
	z-index: 0;
}